Select the correct answer. adam placed an order with an online clothing store. he ordered 5 shirts and 4 pairs of shoes, and he paid $155. his friend ordered 3 shirts and 2 pairs of shoes. his bill totaled $85. assume that all of the shirts are the same price and all of the shoes are the same price. what is the cost of one shirt and one pair of shoes? a. a shirt costs $10, and a pair of shoes cost $25. b. a shirt costs $15, and a pair of shoes costs $20. c. a shirt costs $20, and a pair of shoes costs $15. d. a shirt costs $25, and a pair of shoes cost $10.